Canon EF 70-200mm f/2.8L USM is a telephoto zoom lenses. The lens features 70-200mm at focal length with maximum aperture of f/2.8. The lens construction has 18 elements in 15 groups and has diagonal angle of view at 34 to 12 degrees. Focus adjustment: Inner focusing system with USM, Closest focusing distance at 4.9 feet and has a filter size of 77mm. The Canon EF 70-200mm f/2.8L USM lens weighs 2.9 pounds and it measures 3.3 inches in diameter and 7.6 inches long.